Misuse of Like and As.

The confusion in using like or as is caused by a lack of understanding of the word’s role. Like is used as a preposition, telling where, when or how the noun in the sentence is doing whatever it may be doing. As is used like a conjunction, joining two clauses. A general rule-of-thumb is that like should be followed by an object (to make a prepositional phrase), and as should be followed by a clause containing a verb.

Like

Most of the time, “like” compares two things.

Imagine a grown woman acting as a child.

Here, we’re comparing two things (the woman and the child), so like should be used.

Imagine a grown woman acting like a child.

The same goes for this next sentence where we’re comparing the mother and the girl:

The little girl, as her mother, has bright red hair.

Even though this sentence has a verb after as, the verb has belongs to the first clause, The little girl has bright red hair. We need the adverb like to modify her mother.

The little girl, like her mother, has bright red hair.

As

Frequently, as can be replaced by the way.

No one makes chocolate cake like my mother does.

Because there is a verb after like (does), the conjunction as should be used. It’s easy to say that about this sentence because as can be replaced by the way.

No one makes chocolate cake the way my mother does.

No one makes chocolate cake as my mother does.

He can’t play cricket like he used to.

At first glance, there appears to be no verb after like. However, when speaking, we often leave out verbs which are already implied. The implied verb is play, as in he used to play cricket. Like should be changed to as.